SOURCE ROCKS OF THE CALEDONIAN-AGE GRANITOID ROCKS IN WANYANSHAN-ZHUGUANGSHAN, SOUTHEAST CHINA .2. TOPOLOGICAL ANALYSIS IN ISOTOPIC MULTISPACE

Topological analysis in Sr-Nd-O-Pb3 six-dimensional isotopic space sug gests that the source rocks of the Caledonian-age granitoid rocks in W anyangshan-Zhuguangshan, southeast China, comprise three end-member co mponents. Isotopic mixing model discrimination indicates that the gran itoid rocks were produced through mixing of the three components-in va rying proportions. Comprehensive study of multiple isotopic systems an d geochemistry of the granitoid rocks suggests that the three end-memb er components were crustal rocks which are continent-derived sediments , geosycline sediments and altered basic volcanic rocks.